Josh Larsen’s review published on Letterboxd:
Lamb, about an Icelandic farming couple who take in a half-human, half-sheep baby mysteriously born to one of their livestock, is deadly serious. And that choice by first-time feature director Valdimar Jóhannsson—to not even tiptoe toward anything that could be construed as a wink—is why the movie works. From the opening image, a deceptive POV shot that subtly turns the tables on what we perceive to be the threat, to the stone-faced performances from Noomi Rapace and Hilmir Snær Guðnason in the leads, the movie proceeds with a slowly (very slowly) building dread that stifles any laughter—even when Ada, as the child is named, begins walking around with her lamb’s head poking out of woolly sweaters. Jóhannsson and cinematographer Eli Arenson scour some of the same volcanic landscapes that defined the similarly sheep-adjacent Rams to establish a gorgeously haunting backdrop, especially whenever a mist descends on this valley farm, lending the scenery a fairy-tale eeriness. (You’ll spend much of the movie peering into the screen, asking yourself, “Did I just see that?”) Indeed, Lamb—which begins with a sacrilegious smirk by implying the child of the title was conceived on Christmas—slowly transitions into something more akin to a horrible moral fable. If you can get on its moodily monstrous wavelength, the movie will have you asking why we let some animals sleep on our beds and put others in pens (and occasionally eat them for Christmas dinner).